When it comes to selecting a touchscreen for a new device manufacturers currently have two clear choices: resistive or capacitive. Resistive relies on pressure being applied to the screen and usually works best with pen-based input. Capacitive is the choice of smartphones and uses the body’s electrostatic field measured through a change in capacitance to gauge touch input.

While capacitive is seen as the better tech for most devices, it does block the use of other input devices such as a pen. Quanta Computer and 3M have teamed up to produce a new touchscreen technology that should allow both finger and pen to work well due to a much higher sensitivity.

The new touchscreen technology, being shown off at Computex 2010, is called Dispersive Signal Technology (DST), and relies on an extra layer of glass being used in the display. That glass layer is covered in sensors that pick up pressure, but the sensitivity of the new screen is high enough that finger input should be on a par with capacitive touchscreen solutions, if not higher.

Qaunta has said that the extra layer of glass will have little impact on the thickness of the screen and that the cost of the new tech will be similar to existing solutions.

From using both resistive and capacitive touchscreens capacitive is the clear winner for finger input. That may be fine for smartphones and small tablets, but what about if you have a multifunction large-screen device you want to write notes on? Having the option of pen input would be nice in such situations.

DST looks like it might offer the best of both worlds. Finger input as responsive as that found on existing smartphones like the iPhone, but the ability to pick up a pen and start writing too. The fact it costs the same as existing tech also removes a barrier to its use in new devices.

Until we see DST in action we can’t say if it is a successor to capacitive and resistive touchscreens, but you can be sure companies like Apple and Google will look into using DST in future products if it lives up to the hype.